diff --git a/core/base/Dockerfile b/core/base/Dockerfile
index 892faa9b..842fd89b 100644
--- a/core/base/Dockerfile
+++ b/core/base/Dockerfile
@@ -3,7 +3,7 @@
 # base system image (intermediate)
 # Note when updating the alpine tag, first manually run the workflow .github/workflows/mirror.yml.
 # Just run the workflow with the tag that must be synchronised.
-ARG DISTRO=ghcr.io/mailu/alpine:3.21.0
+ARG DISTRO=ghcr.io/mailu/alpine:3.21.4
 FROM $DISTRO as system
 
 ENV TZ=Etc/UTC LANG=C.UTF-8